Journal of Food Processing & Technology

Abstract

Specific Energy Consumption in Convective-microwave Drying of Ashwagandha (Withania Somnifera) Roots

Ashok K Senapati, Rao PS, Lalit M Bal and Suresh Prasad

Evaluation of specific energy consumption was carried out during convective-microwave and convective drying of Ashwagandha root in a developed laboratory scale microwave dryer. The specific energy consumption in convective drying at 60ºC of air temperature and 1.0 m/s air velocity was estimated as 2.27 ± 0.12) MJ/kg of water evaporated. The increase in air velocity increased the energy consumption. The specific energy consumption at 6 W/g of microwave power level, 60ºC air temperature and 1.0 m/s air velocity was 0.396 ± 0.047) MJ/kg of water evaporated, resulting in about 82% energy saving as compared to convective drying processes. The drying time increased with increase in air velocity in convective - microwave drying process as a reverse trend that was observed in convective drying process of Ashwagandha roots.